Multiple types of separate valves have been used in commercial practice to control fluid flow in pipes, hoses, and tubes. Ball valves are used as a shut off valve to cut off fluid flow. Check valves are used to prevent back flow of fluid, for example due to a downstream loss of pressure. Pressure and flow regulating valves are used to maintain outlet flow from the valve within acceptable limits.
Existing valves, such as ball valves, check valves, and pressure and flow regulating valves, typically make extensive use of metal or other materials in their valve bodies, which may be expensive. Systems incorporating separate valves for various functions, such as a separate ball valve and a check valve connected to the outlet of the ball valve, or a separate ball valve and flow regulating valve, require relatively large amounts of material and associated costs. Systems combining a ball valve and check valve typically require a larger valve body to accommodate a combined valve and suffer from similar problems as separate ball valves and check valves.